"shallow dish. Patella The patella, also known as the kneecap, is a thick, circular-triangular bone which articulates with the femur (thigh bone) and covers and protects the anterior articular surface of the knee joint. The patella is found in many tetrapods, such as mice, cats and birds, but not in whales, or most reptiles. In humans, the patella is the largest sesamoid bone in the body. Babies are born with a patella of soft cartilage which begins to ossify into bone at about three years of age. The patella is a sesamoid bone roughly triangular in shape, with the apex"
"has been rejected. Partite patellas occur almost exclusively in men. Tripartite and even multipartite patellas occur. The upper three-quarters of the patella articulates with the femur and is subdivided into a medial and a lateral facet by a vertical ledge which varies in shape. Four main types of articular surface can be distinguished: In the patella an ossification centre develops at the age of 3–6 years. The patella originates from two centres of ossification which unite when fully formed. The primary functional role of the patella is knee extension. The patella increases the leverage that the quadriceps tendon can exert"
"patella facing downwards. The apex is the most inferior (lowest) part of the patella. It is pointed in shape, and gives attachment to the patellar ligament. The front and back surfaces are joined by a thin margin and towards centre by a thicker margin. The tendon of the quadriceps femoris muscle attaches to the base of the patella., with the vastus intermedius muscle attaching to the base itself, and the vastus lateralis and vastus medialis are attached to outer lateral and medial borders of patella respectively. The upper third of the front of the patella is coarse, flattened, and rough,"
"is defined as trochlear dysplasia. Not having a groove because the trochlear bone has flattened out can cause the patella to slide because nothing is holding the patella in place. Patellar dislocations occur by: The patella is a triangular sesamoid bone which is embedded in tendon. It rests in the patellofemoral groove, an articular cartilage-lined hollow at the end of the thigh bone (femur) where the thigh bone meets the shin bone (tibia). Several ligaments and tendons hold the patella in place and allow it to move up and down the patellofemoral groove when the leg bends. The top of"
"present in the living monotremes, the platypus and the echidna. In more primitive tetrapods, including living amphibians and most reptiles (except some Lepidosaurs), the muscle tendons from the upper leg are attached directly to the tibia, and a patella is not present. In 2017 it was discovered that frogs have kneecaps, contrary to what was thought. This raises the possibility that the kneecap arose 400 million years ago when tetrapods first appeared, but that it disappeared in some animals. The word ""patella"" originated in the late 17th century from the diminutive form of Latin ' or ' or ""paten"", meaning"
"Patellar ligament The patellar ligament is the distal portion of the common tendon of the quadriceps femoris, which is continued from the patella to the tibial tuberosity. It is also sometimes called the ""patellar tendon"" as it is a continuation of the quadriceps tendon. The patellar ligament is a strong, flat, ligament, which originates on the apex of the patella distally and adjoining margins of the patella and the rough depression on its posterior surface; below, it inserts on the tuberosity of the tibia; its superficial fibers are continuous over the front of the patella with those of the tendon"
"knee. These fractures usually cause swelling and pain in the region, bleeding into the joint (hemarthrosis), and an inability to extend the knee. Patella fractures are usually treated with surgery, unless the damage is minimal and the extensor mechanism is intact. An exostosis is the formation of new bone onto a bone, as a result of excess calcium formation. This can be the cause of chronic pain when formed on the patella. The patella is found in placental mammals and birds; most marsupials have only rudimentary, non-ossified patellae although a few species possess a bony patella. A patella is also"
"Type 2: Fragment is located on the lateral side of the kneecap (20% of cases) Type 3: Fragment is located on the upper lateral border of the kneecap (75% of cases) Bipartite patella Bipartite patella is a condition where the patella, or kneecap, is composed of two separate bones. Instead of fusing together as normally occurs in early childhood, the bones of the patella remain separated. The condition occurs in approximately 12% of the population and is nine times more likely to occur in males than females. It is often asymptomatic and most commonly diagnosed as an incidental finding, with"
"plexus patellae. The infrapatellar branch is occasionally small, and ends by joining the anterior cutaneous branches of the femoral, which supply its place in front of the knee. Infrapatellar branch of saphenous nerve The infrapatellar branch of saphenous nerve is a nerve of the lower limb. The saphenous nerve, located about the middle of the thigh, gives off a branch which joins the subsartorial plexus. It pierces the sartorius and fascia lata, and is distributed to the skin in front of the patella. This nerve communicates above the knee with the anterior cutaneous branches of the femoral nerve; below the"
"of age. Due to the great stress on the patellofemoral joint during resisted knee flexion, the articular cartilage of the patella is among the thickest in the human body. The lower part of the posterior surface has vascular canaliculi filled and is filled by fatty tissue, the infrapatellar fat pad. Emarginations (i.e. ""patella emarginata"", a ""missing piece"") are common laterally on the proximal edge. Bipartite patellas are the result of an ossification of a second cartilaginous layer at the location of an emargination. Previously, bipartite patellas were explained as the failure of several ossification centres to fuse, but this idea"
"and serves for the attachment of the tendon of the quadriceps and often has exostoses. The middle third has numerous vascular canaliculi. The lower third culminates in the apex which serves as the origin of the patellar ligament. The posterior surface is divided into two parts. The upper three-quarters of the patella articulates with the femur and is subdivided into a medial and a lateral facet by a vertical ledge which varies in shape. In the adult the articular surface is about and covered by cartilage, which can reach a maximal thickness of in the centre at about 30 years"
"Infrapatellar branch of saphenous nerve The infrapatellar branch of saphenous nerve is a nerve of the lower limb. The saphenous nerve, located about the middle of the thigh, gives off a branch which joins the subsartorial plexus. It pierces the sartorius and fascia lata, and is distributed to the skin in front of the patella. This nerve communicates above the knee with the anterior cutaneous branches of the femoral nerve; below the knee, with other branches of the saphenous; and, on the lateral side of the joint, with branches of the lateral femoral cutaneous nerve, forming a plexiform net-work, the"
"Bipartite patella Bipartite patella is a condition where the patella, or kneecap, is composed of two separate bones. Instead of fusing together as normally occurs in early childhood, the bones of the patella remain separated. The condition occurs in approximately 12% of the population and is nine times more likely to occur in males than females. It is often asymptomatic and most commonly diagnosed as an incidental finding, with about 2% of cases becoming symptomatic. Saupe introduced a classification system for Bipartite Patella back in 1921. Type 1: Fragment is located at the bottom of the kneecap (5% of cases)"
"Medial patellofemoral ligament The medial patellofemoral ligament (or MPFL) is one of the several ligaments on the medial aspect of the knee. It originates on the superomedial aspect of the patella and inserts in the space between the adductor tubercle and the medial femoral epicondyle. Its main function is to prevent lateral displacement of the patella. The MPFL is the primary stabilizer to lateral displacement of the patella providing approximately 50-60% of restraining force. Injury to the MPFL is most common during a non-contact twisting action. The most likely time for the patella to shift laterally is during the first"
"Patella fracture A patella fracture is a break of the kneecap. Symptoms include pain, swelling, and bruising to the front of the knee. A person may also be unable to walk. Complications may include injury to the tibia, femur, or knee ligaments. It typicals results from a hard blow to the front of the knee or falling on the knee. Occasionally it may occur from a strong contraction of the thigh muscles. Diagnosis is based on symptom and confirmed with X-rays. In children an MRI may be required. Treatment may be with or without surgery, depending on the type of"
"the patella attaches to the quadriceps muscle via the quadriceps tendon, the middle to the vastus medialis obliquus and vastus lateralis muscles, and the bottom to the head of the tibia (tibial tuberosity) via the patellar tendon, which is a continuation of the quadriceps femoris tendon. The medial patellofemoral ligament attaches horizontally in the inner knee to the adductor magnus tendon and is the structure most often damaged during a patellar dislocation. Finally, the lateral collateral ligament and the medial collateral ligament stabilize the patella on either side. Any of these structures can sustain damage during a patellar dislocation. To"
"assess the knee, a clinician can perform the patellar apprehension test by moving the patella back and forth while the people flexes the knee at approximately 30 degrees. The people can do the ""patella tracking assessment"" by making a single leg squat and standing, or by lying on his or her back with knee extended from flexed position. A patella that slips laterally on early flexion is called the , and indicates imbalance between the VMO and lateral structures. The patella is a floating sesamoid bone held in place by the quadriceps muscle tendon and patellar tendon ligament. Exercises should"
"palm as the palma and palmar, the thumb as the pollex, and the fingers as the digits, phalanges, and phalangeal. The buttocks are the gluteus or gluteal region and the pubic area is the pubis. Anatomists divide the lower limb into the thigh (the part of the limb between the hip and the knee) and the leg (which refers only to the area of the limb between the knee and the ankle). The thigh is the femur and the femoral region. The kneecap is the patella and patellar while the back of the knee is the popliteus and popliteal area."
"Patellar dislocation A patellar dislocation is a knee injury in which the patella (kneecap) slips out of its normal position. Often the knee is partly bent, painful and swollen. The patella is also often felt and seen out of place. Complications may include a patella fracture or arthritis. A patellar dislocation typically occurs when the knee is straight and the lower leg is bent outwards when twisting. Occasionally it occurs when the knee is bent and the patella is hit. Commonly associated sports include soccer, gymnastics, and ice hockey. Dislocations nearly always occur away from the midline. Diagnosis is typically"
"on the femur by increasing the angle at which it acts. The patella is attached to the tendon of the quadriceps femoris muscle, which contracts to extend/straighten the knee. The patella is stabilized by the insertion of the horizontal fibres of vastus medialis and by the prominence of the lateral femoral condyle, which discourages lateral dislocation during flexion. The retinacular fibres of the patella also stabilize it during exercise. Patellar dislocations occur with significant regularity, particular in young female athletes. It involves the patella sliding out of its position on the knee, most often laterally, and may be associated with"
"Plica syndrome Plica syndrome (also known as synovial plica syndrome) is a condition that occurs when a ""plica"" (a vestigial extension of the protective synovial capsule of the knee) becomes irritated, enlarged, or inflamed. This inflammation is typically caused by the plica being caught on the femur, or pinched between the femur and the patella. The most common location of plica tissue is along the medial (inside) side of the knee. The plica can tether the patella to the femur, be located between the femur and patella, or be located along the femoral condyle. If the plica tethers the patella"
"Luxating patella Luxating patella (or trick knee, subluxation of patella, floating patella, or floating kneecap) is a condition in which the patella, or kneecap, dislocates or moves out of its normal location. Patella luxation is a common condition in dogs, particularly small and miniature breeds. The condition usually becomes evident between the ages of 4 and 6 months. It can occur in cats, as well, especially domestic short-haired cats. It also occurs in humans, where it can be associated with damage to the anterior cruciate ligament. Most cases of patellar luxation are medial, and this is frequently a congenital problem"
"from inferior edges of the mensici to the periphery of the tibial plateaus. The patellar ligament connects the patella to the tuberosity of the tibia. It is also occasionally called the patellar tendon because there is no definite separation between the quadriceps tendon (which surrounds the patella) and the area connecting the patella to the tibia. This very strong ligament helps give the patella its mechanical leverage and also functions as a cap for the condyles of the femur. Laterally and medially to the patellar ligament the lateral and medial retinacula connect fibers from the vasti lateralis and medialis muscles"
"of surgery. This patellar ligament method of reconstruction was traditionally the gold standard graft for anterior cruciate ligament reconstruction, and is still one of the more preferred methods. Its insertion on the tibia is the location of Osgood–Schlatter disease. Patellar ligament The patellar ligament is the distal portion of the common tendon of the quadriceps femoris, which is continued from the patella to the tibial tuberosity. It is also sometimes called the ""patellar tendon"" as it is a continuation of the quadriceps tendon. The patellar ligament is a strong, flat, ligament, which originates on the apex of the patella distally"
"Palatine bone The palatine bones () are two irregular bones of the facial skeleton in many animal species. Together with the maxillae they comprise the hard palate. (""Palate"" is derived from the Latin ""palatum"".) The palatine bones are situated at the back of the nasal cavity between the maxilla and the pterygoid process of the spenoid bone. They contribute to the walls of three cavities: the floor and lateral walls of the nasal cavity, the roof of the mouth, and the floor of the orbits. They help to form the pterygopalatine and pterygoid fossae, and the inferior orbital fissures. Each"
"and adjacent fibula, and these are all long bones. The patella (kneecap) is the sesamoid bone in front of the knee. Most of the leg skeleton has bony prominences and margins that can be palpated and some serve as anatomical landmarks that define the extent of the leg. These landmarks are the anterior superior iliac spine, the greater trochanter, the superior margin of the medial condyle of tibia, and the medial malleolus. Notable exceptions to palpation are the hip joint, and the neck and body, or shaft of the femur. Usually, the large joints of the lower limb are aligned"
"than 25 degrees between the patellar tendon and quadriceps muscle can predispose a person to patellar dislocation. In patella alta, the patella sits higher on the knee than normal. Normal function of the VMO muscle stabilizes the patella. Decreased VMO function results in instability of the patella. When there is too much tension on the patella, the ligaments will weaken and be susceptible to tearing ligaments or tendons due to shear force or torsion force, which then displaces the kneecap from its origination. Another cause that patellar dislocation can occur is when the trochlear groove that has been completely flattened"
"Pain at the lateral femoral condyle is suggestive of iliotibial band syndrome. Swelling at the popliteal fossa may reveal a Baker's cyst. The absence of normal grooves around patella may indicates a patellar intra-articular effusion. There are two ways to confirm the effusion. The knee is extended fully before the examination begins. This first way is the patellar tap. It is to squeeze the fluid between the patella and the femur by pressing at the medial patella using a non-dominant hand. Then, using the dominant hand to press on the patella vertically. If the patella is ballotable, then patellar intra-articular"
"extremely intense pain and swelling. The patella can be tracked back into the groove with an extension of the knee, and therefore sometimes returns into the proper position on its own. A ""patella alta"" is a high-riding (superiorly aligned) patella. An attenuated patella alta is an unusually small patella that develops out of and above the joint. A ""patella baja"" is a low-riding patella. A long-standing patella baja may result in extensor dysfunction. The kneecap is prone to injury because of its particularly exposed location, and fractures of the patella commonly occur as a consequence of direct trauma onto the"
"stifle joint in different species. These sesamoids assist with the smooth movement of tendon/muscle over the joint. The most well-known sesamoid bone is the patella, more commonly known as the 'knee cap'. It is located cranially to the joint and sits in the trochlear groove of the femur. It guides the patellar ligament of the quadriceps over the knee joint to its point of insertion on the tibia. Caudal to the joint, in the dog for example, are the two fabellae, which lie in the two tendons of origin of gastrocnemius. Fourth, there is often a small sesamoid bone in"
"rupture occurs, the patella loses support from the tibia and moves toward the hip when the quadriceps muscle contracts, hindering the leg's ability to extend. This means that those affected cannot stand, as their knee buckles and gives way when they attempt to do so. The upper part of the patellar tendon attaches on the lower part of the knee cap, and the lower part of the patella tendon attaches to the tibial tubercle on the front of the tibia. Above the knee cap the quadriceps muscle via the quadriceps tendon attaches to the top of the knee cap. This"
"Baculum The baculum (also penis bone, penile bone, or os penis, or os priapi) is a bone found in the penis of many placental mammals. It is absent in the human penis, but present in the penises of other primates, such as the gorilla and chimpanzee. The bone is located above the male urethra, and it aids sexual reproduction by maintaining sufficient stiffness during sexual penetration. The homologue to the baculum in female mammals is known as the baubellum or os clitoridis – a bone in the clitoris. The word ""baculum"" meant ""stick"" or ""staff"" in Latin and originated from"
"Interparietal bone An interparietal bone (os interparietale or Inca bone or os Inca. Var.) is a dermal bone situated between the parietal and supraoccipital. In humans, it corresponds to the upper portion of the squama of the occipital bone that lies superior to the highest nuchal line and is completely fused to the supraoccipital. However, in some individuals this portion remains separate from the rest of the occipital bone throughout life. In such cases, this separate bone is particularly referred as Inca bone. Inca bones in humans were first found in the skulls of contemporary indigenous peoples of the southern"